1. Field of the Invention
The invention relates generally to combustion heaters and is more specifically directed to portable stoves or furnaces which may be employed for radiant space heating and especially, in combination with suitable containers, for cooking foodstuffs and for heating water with combustible materials under relatively primitive conditions.
2. Description of the Prior Art
The heater/cooker invention set forth herein represents evolutionary advance over the prior art disclosed in U.S. Pat. No. 4,722,322 for "High Efficiency Combustion Heater" dated Feb. 2, 1988. This prior art patent sets forth the technology underlying inventive means by which, in a simple field stove, both combustion of fuels such as wood and transfer of heat from such combustion to a pot for cooking or water heating may be effected with unusually high efficiency. The generic inventive concept is also related to a space heater employing radiant heat as its primary mode of transfer of thermal energy from burning fuel to the surroundings or to individuals in the vicinity.
Numerous carefully controlled tests of these prior art devices for cooking and water heating in a pot have demonstrated system efficiencies in the range of 30% to over 40% determined by measuring temperature rise in a known mass of water resulting from burning a known weight of fuelwood of known heating value per pound. This heating efficiency is .. on the order of 4 to 5 times the efficiency of water heating in a pot over an open fire under commonly encountered conditions.
In the course of conducting the above-noted efficiency tests a number of improvements relating to utility, practicability and especially producibility were found important to practice of the art, notably in developing regions where the advances of powered machine fabrication are limited or non-existent. The present invention is directed to such improvements while preserving the high efficiencies demonstrated by the above-cited prior art devices.